Insects, particularly mosquitoes, carry diseases and are generally regarded as pests to both animals and plants. Every year, over one million people worldwide die from mosquito-borne diseases. Mosquitoes can carry many different kinds of diseases including malaria, heartworm, dengue fever, encephalitis, yellow fever and West Nile virus.
Because of the health concerns and discomfort related to insect bites and stings, insecticides, which kill insects, or repellents, which merely repel insects, are commonly used to keep insects away from animals, plants and building structures. However, commercially available insecticides, including those available for home use, commonly include active ingredients which are not only toxic to the target pests, but, if used in relatively confined environments and delivered as aerosol sprays, can be present in sufficient concentration to be toxic to humans and household pets. Various undesirable side effects may include immediate or delayed neurotoxic reactions and/or suffocation. Even the noxious odor of such materials can cause headaches or nausea in some individuals. These adverse side effects are exacerbated when such compositions come in contact with persons of increased sensitivity, or persons of small body mass such as children or babies.
Therefore, efforts have been made to develop insecticidal compositions, particularly those intended for residential use in aerosol form, which are effective in killing the targeted insect pests completely and quickly, but which are non-poisonous to humans and pets. Unfortunately, non-poisonous insecticidal compositions available heretofore have had limited efficacy. Attempts to use essential oils as the active ingredient in such insecticides, while having limited success, have generally been found to be either cost prohibitive, inadequately lethal to control a range of targeted insect pest species, or too slow-acting to enable the user to confirm that the insect has been killed and to dispose of the dead insect so as to avoid polluting the environment.
Furthermore, although insecticides, which kill the target pests, are usually the quickest forms of treatment, they kill not only the undesired insects, but beneficial insects as well. Therefore, insect repellents may be a compromise that minimizes disease and discomfort in animals and plants, without disrupting the natural balance of insects.
Accordingly, what is needed are new formulations useful for effectively repelling pests, including insects, from animals, plants and building structures. The formulations should be long lasting and of lesser toxicity than traditional repellents.
Additionally, effective repellents are needed to reduce the transmission of infectious disease. Because insects are also carriers of infectious diseases, a repellent composition the prevents or reduces the number of landings and bites of insects may reduce the transmission of infectious diseases.